Tuesday was Ottawa's hottest October day on record

Oct. 3, 2023, was Ottawa's hottest October day in more than 150 years of Environment Canada records.

Environment Canada said the temperature reached 30.9 C at Ottawa's international airport on Tuesday.

The hottest October temperature in records going back to 1872for Ottawa was 29.4 C, reached twice in the 1890s. Thehottest autumn temperature on record was 33 C in late September 2017.

The average high temperature in Ottawa forOct. 4 is 15 C and the average low is about 5 C, according to Environment Canada. Tuesday's low was 15 C.

Petawawa's 30.6 C on Tuesday was also a monthly record there, according to Environment Canada. Gatineau and Maniwaki set daily records.

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Ottawa reached 30 CWednesday, breakingthe Oct. 4 record of 27.7 C from 2005.

Daily records were also set in places such as Belleville, Cornwall, Kemptville andStirling.

Human activity is causing climate change that makes extreme heat more likely,placing vulnerable people, businesses, infrastructure and agriculture at further risk.

The unseasonable heat shouldn't trigger a proper heat warning from Environment Canada, which issues them when at least two days in a row above 30 C and nights above 20 C are forecast, or when humidity is expected to make it feel like 40 two days in a row.

Humidity is expected to make it feel like 35 Wednesday in the capital.

The forecast calls for Ottawa to reach 26 C Thursday and thenfall back to moreseasonal temperatures through a wetter Thanksgiving weekend.

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